1. Field of Invention
The present invention relates to a billboard and control method thereof, and more particularly to a large elevating billboard and control method thereof, wherein the elevating billboard is easy to assemble, disassemble or maintain.
2. Description of Related Arts
Billboards are used as devices to transmit advertising information to the public, and according to different need, the billboards can be made into various forms. Among that the large billboards which are established on transport corridors, transport hubs and so on are more common, the billboard stent of the billboards are usually supported on single column or multiple columns, and according to the billboard face, the billboards can be divided into single-face, double-face, multiple-face. Because such billboards have simple structure, easy production process and can attract the attention of passers, the billboards are widely used. However, in actual use, it is found that: because the billboard stent is fixed with the column, the workers and the equipments work on a high altitude when the billboards are assembled, disassembled, maintained or replaced in use, clearly on the one hand, this brings a great deal of inconvenience to operation, on the other hand, it brings security risk to the workers. And in windy weather, the billboards which have a high position cannot change their own height with the wind, therefore it is easy to damage the billboards, and even the columns fall in bad weather, which does not only bring unnecessary loss to the advertisers and manufacturers, but also brings great security risk to the pedestrians. In order to eliminate such defect, it is tended to increase the size of the column, improve the material of the billboard stent and so on to meet the wind load in windy weather, however, this program will obviously increase the manufacture cost of the billboards.
For the current situation, someone designs an elevating billboard, such as an elevating billboard, according to Chinese patent, Publication No. CN200969193Y, the elevating billboard comprises at least a pair of main columns, a supporting assembly for fixing the main column, and a pair of telescopic cylinders fixed with the corresponding main column, wherein each telescopic cylinder consists of link antenna-style multistage cylinder, a face is disposed between two corresponding telescopic cylinders. In use, the face is mounted on a lower position through the telescopic cylinders, and then the face is risen to a high position in order to overcome the danger of working on a height and the inconvenience of assembly and disassembly. However, in actual operation, after the face is mounted on the top telescopic cylinder, it is needed to draw out the top telescopic cylinder from the lower telescopic cylinder. Apparently, it is laborious and time-consuming to complete this operation, especially, when such operation is used in large billboard, it is extremely difficult to complete the operation by manual work, and it is slow to complete the up and down movement of the billboards by manual assembly and disassembly, which does not make rapid response in time by wind scale, so this kind of billboards needs to be further improved.